Various bench or table type machines such as planers, jointers, and circular saws possess adjustable infeed and outfeed tables so as to maintain a consistent reference between the cutting tool and the workpiece that is generally being fed into the material cutting or removal apparatus. Whether the cutting tool is disposed above the workpiece or below, it has long been accepted by the craftsmen using such machines that any variation in the aforementioned tool-workpiece disposition could result in the asymmetrical removal of material from the workpiece. Thus, whether the machine in use be a planer, jointer or sawing mechanism, and whether the cutting tool be disposed above or below the workpiece, relative adjustments between infeed and outfeed tables must often be made to assure a consistent, uniform presentation of the workpiece to the cutting tool.
Turning to the more specific areas of concern in the instant invention, adjustability of an infeed or outfeed extension for the table or bench type planer offers considerable promise for alleviating an onerous problem that has faced craftseen for years. Although a significant amount of art exists, drawn to adjustability of infeed and outfeed tables, there is a paucity of invention dealing with the production or use of infeed/outfeed table extensions of the variable or adjustable type. The teachings of Morris, as disclosed in U.S. Pat. No. 1,104,735, address the need for a variable or adjustable infeed table extension. The Morris disclosure shows an extension to the infeed table of a saw. That the main work platform or saw table moves to transport work into the cutting tool is of no immediate consequence; however, Morris employs the aforesaid apparatus to either present an infeed table at the height of the translating saw table or in an inoperative position, below the saw table, for ripping operations. Essentially, this infeed extension rests on rocking arms that extend from a horizontal support which is supported at the adjustable table's infeed end by a fixed, but manually adjustable, vertical stanchion. The outfeed end of the extension table is journaled to the infeed end of the saw table. The actual extension table surface is cantilevered by rocking arms from the horizontal support and further supported at its swinging edge by a vertical, two-position height adjustable leg. Height adjustability in the vertical leg is acquired through use of a hand operated knuckle joint which is caused to move between two stationary holding pins, one which will effect a shortening of the knuckle joint adjustment leg and the other which effects a lengthening of it. When the knuckle joint is manually adjusted to retract the out-rigged extension leg, the infeed extension table pivots on its rocker extension and is caused to drop below the level of the saw table. When the knuckle joint is adjusted to acquire the longer extension, the infeed extension table is raised to the height of the saw table. It is apparent to one of ordinary skill in the art that this infeed extension table could be made to serve as an outfeed extension table, as well. What is also apparent, as a drawback or disadvantage of the invention, is the lack of continuous adjustability in that it can only be positioned in one of two postures; compounding this disadvantage is the fact that the adjustment must be made manually and that the inventor really did not contemplate its use as an outfeed table extension. The Morris invention, save for its basic concept of providing an adjustable infeed or outfeed table, does not fulfill the instant inventor's need for an automatically adjustable infeed/outfeed extension.
When heavy, elongate workpieces are fed into a planer, jointer, or the like, it may be necessary to make an adjustment in the machine's working surface. Such a necessity has been cleverly dealt with in the industry as attested to in the patent issued to Boice, U.S. Pat. No. 3,171,454, in 1965. The Boice teaching provides a means for adjusting the positions of jointer cutters to achieve this, in part; the machine work table is distinctly divided between outfeed and infeed tables. The input side, or cutting side, of the outfeed table is fashioned with incline means while the output or cutting side of the infeed table is constructed with an incline surface having the compliment of the outfeed incline surface and in slidable registry therewith. By causing one of the tables, here the infeed table, to move into or away from the other, along their common longitudinal axis, the moving table either "rides up" or "rides down" the incline end of the other table, thus being raised or lowered, respectively. Although Boice does not deal with the subject of infeed or outfeed extension tables, he nevertheless employed a clever means for effecting upward and downward translation of a table and, therefore, teaches an element of the art considered relevant by the instant inventor.
An outfeed extension table and, to some degree, an infeed extension table must be maintained at a consistent height, relative the cutting tool. The longer the workpiece, and the heavier, the more this factor becomes apparent to the craftsman. For example, if a carpenter were working a long two by eight on a planer or jointer, as the workpiece passed the end of the outfeed table, its weight would begin to cause a bowing running from the edge of the outfeed table to the closest secondary fulcrum, the cutting tool. Thus, an unexpected and unwanted force would be applied to the workpiece forcing it either into or away from the cutting tool. But if an extension table were provided so that a contiguous infeed or outfeed surface is provided for the elongate workpiece, and that extension (specifically, its surface farthest from the cutting tool), is maintained at the same height as the infeed or outfeed table, the aforementioned problem would be successfully avoided.
Thus, the instant inventor sought to provide an automatically adjusting infeed/outfeed extension table for machines of the types herein mentioned. Specifically, the ends of the extension tables nearer the respective infeed/outfeed tables were to be fixed or journaled to those respective tables while the outermost ends of the extension tables would be adjustably motivated so as to remain at the precise heights of the respective infeed/outfeed table surfaces which they served. As hereinafter disclosed and described, the instant inventor has conceived and reduced to practice a most useful invention embodying the aforesaid concepts.